Friction stir welding apparatus, system and method

Abstract

A method of performing friction stir welding is provided herein. More specifically, traditional friction stir welding requires a rotatable head that is forced against a plurality of work pieces to bond the same. The rotational and normal forces generated by the friction stir welding tool are generally reacted by a backing plate, anvil, mandrel or other mechanisms, such hardware are subject to the applied forces and are often supported with additional internal supports. Conversely, a method of performing a friction stir weld is described that omits the need for such a backing member and internal supports as it is performed using a self reacting pin tool.

What is claimed is: 
     
       1. A method for performing circumferential stir welding comprising:
 providing first and second cylindrical components abutted to one another forming a seam; 
 providing a first ring assembly positioned adjacent to a first end of the first cylindrical component and in contact with the first cylindrical component; 
 providing a second ring assembly positioned adjacent to a second end of the first cylindrical component, said second assembly comprising an inner ring interconnected to an outer ring and the inner ring placed in contact with the first cylindrical component; 
 providing a third ring assembly positioned adjacent to a first end of the second cylindrical component opposite from said first ring assembly, said third ring assembly comprising an inner ring interconnected to an outer ring and the inner ring placed in contact with the second cylindrical component; 
 providing at least one linkage that interconnects the first ring assembly to the second ring assembly; 
 orienting the first and second cylindrical components to be stacked vertically with respect to one another; 
 providing at least one stand that supports the third ring assembly; 
 rotating the first, second, and third ring assemblies relative to a weld assembly positioned externally of said cylindrical components that welds the first cylindrical component to the second cylindrical component by friction stir welding, wherein the weld is created horizontally to join the vertically stacked cylindrical components. 
 
     
     
       2. A method, as claimed in  claim 1 , further including:
 providing a self-reacting pin tool for said weld assembly, said self-reacting pin tool being used for the friction stir welding of said first and second cylindrical components along said seam to join said first cylindrical component to said second cylindrical component. 
 
     
     
       3. A method, as claimed in  claim 1 , further including:
 providing the first ring assembly with an inner ring interconnected to an outer ring by way of a center ring; and 
 engaging an edge of either said first and second cylindrical component with a capture hook. 
 
     
     
       4. A method, as claimed in  claim 1 , wherein:
 said first, second and third ring assemblies are rotated relative to a weld assembly by a turntable.